hare

commit 0b23719c9f128b183c427a9a3c182f2f96195e58
parent c6151b58d1f2fccf006d9ac33cea7f4c835b8dbe
Author: Sebastian <sebastian@sebsite.pw>
Date:   Mon,  7 Mar 2022 22:35:10 -0500

parse: permit trailing comma in switch case

	case foo, bar, =>

This is already allowed by the specification and accepted by harec.

Signed-off-by: Sebastian <sebastian@sebsite.pw>

Diffstat:
M
hare/parse/expr.ha
 | 
15
+++++++--------

1 file changed, 7 insertions(+), 8 deletions(-)
diff --git a/hare/parse/expr.ha b/hare/parse/expr.ha
@@ -1014,17 +1014,16 @@ fn switch_expr(lexer: *lex::lexer) (ast::expr | error) = {
 		want(lexer, ltok::CASE)?;
 
 		let opts: []*ast::expr = [];
-		if (try(lexer, ltok::ARROW)? is void) {
-			for (true) {
-				append(opts, alloc(expr(lexer)?));
-
-				if (try(lexer, ltok::COMMA)? is void) {
-					want(lexer, ltok::ARROW)?;
+		if (try(lexer, ltok::ARROW)? is void) for (true) {
+			append(opts, alloc(expr(lexer)?));
+			switch (want(lexer, ltok::ARROW, ltok::COMMA)?.0) {
+			case ltok::ARROW =>
+				break;
+			case ltok::COMMA =>
+				if (try(lexer, ltok::ARROW)? is lex::token) {
 					break;
 				};
 			};
-			synassert(lex::mkloc(lexer), len(opts) != 0,
-				"Expected a list of options")?;
 		};
 
 		let exprs: []*ast::expr = [];